Trends in Cognitive Sciences
OpinionThe amygdala and ventromedial prefrontal cortex in morality and psychopathy
Introduction
Care-based morality can be considered as those forms of moral reasoning that concern actions that harm others. Other forms of moral cognition might exist but these will not be considered in detail here (Box 1). Why do we care whether anyone else is hurt? Perhaps equally importantly, why do some people, individuals with psychopathy, care less?
Here, I make reference to the functional roles of the amygdala and ventromedial prefrontal cortex (vmPFC) in the learning and use of reinforcement expectancies (expectancies of reward or punishment). I argue that (i) the integrated functioning of these systems enables the basics of care-based morality; and (ii) dysfunction within these regions in psychopathy means that reinforcement-based decision making, including moral decision making, is impaired.
Moral transgressions (e.g. one person hitting another) are defined by their consequences for the rights and welfare of others. Social conventional transgressions are defined as violations of the behavioral uniformities that structure social interactions within social systems (e.g. dressing in opposite gender clothing). Healthy individuals distinguish conventional and moral transgressions in their judgments from the age of 39 months [1] and across cultures [2]. In particular, moral transgressions are judged to be less rule-contingent than are conventional transgressions; individuals are less likely to state that moral, rather than conventional, transgressions are permissible in the absence of prohibiting rules [3].
Early models of moral socialization suggested unitary accounts of social rule learning, stressing, for example, either punishment [4] or cultural transmission [5]. However, such accounts struggle to explain the existence of the moral–conventional distinction [3]. Moreover, the social consequences of moral and conventional transgressions differ; caregivers are more likely to refer transgressors of moral rules to the consequences of their actions for the victim and transgressors of conventional rules to the rules themselves or the sanctions against prohibition [6].
Early discussions of the development of the moral–conventional distinction itself suggested that it emerged as a function of abstract reasoning processes [3]. They made two clear predictions. First, populations with impaired abstract reasoning should fail to develop the moral–conventional distinction. However, no data have been presented in support of this position. Moreover, at least one population with pronounced executive function impairment, children with autism, pass the moral–conventional distinction [7]. Second, populations who show impairment in the development of the moral–conventional distinction should show impairment in abstract reasoning and/or executive dysfunction. Individuals with psychopathy show significantly less of a moral–conventional distinction than do healthy individuals [8]. However, before considering executive dysfunction in this population, I will briefly consider the nature of psychopathy.
Section snippets
Psychopathy
Psychopathy is a developmental disorder [9] that involves emotional dysfunction, characterized by reduced guilt, empathy and attachment to significant others, and antisocial behavior including impulsivity and poor behavioral control [10]. It is not equivalent to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) psychiatric diagnoses of conduct disorder (CD) and antisocial personality disorder (ASPD), which focus only on the presence of antisocial behavior rather
Psychopathy and morality
Individuals with psychopathy show significantly less of a moral–conventional distinction than do healthy individuals [8]. If the moral–conventional distinction emerged as a function of abstract reasoning processes [3], we might believe that individuals with psychopathy will show impairment in abstract reasoning and/or executive dysfunction. However, no data suggest that they do. Indeed, individuals with psychopathy show executive dysfunction only if the executive function has an affective
Dysfunctional neural systems in psychopathy
The neuropsychological literature on psychopathy has identified two core neural regions that seem to be dysfunctional in psychopathy: the amygdala and the vmPFC. Psychopathy is associated with a series of core functional impairments: deficits in aversive conditioning, the augmentation of the startle reflex by visual threat primes and fearful expression recognition. These impairments are also seen following lesions of the amygdala [25]. In addition, psychopathy is associated with problems in
The amygdala, vmPFC and morality
The amygdala and vmPFC are implicated not only in the emergence of psychopathy, but also in moral reasoning. Thus, the amygdale, and particularly the vmPFC, have frequently been identified in neuroimaging studies of moral reasoning 18, 19, 35 (Figure 1). For example, Greene et al.[19] reported increased vmPFC activity in response to personal as opposed to impersonal moral choices, and the difference between these two situations related effectively to the salience of the victim. Similarly, in
The amygdala
The amygdala is crucial for stimulus-reinforcement learning 38, 39. This learning enables representations of conditioned stimuli within temporal cortex to be linked to emotional responses mediated by the amygdala and other structures (Figure 2). In short, the amygdala enables the individual to learn the goodness and badness of objects and actions. Moreover, because the relationship between the amygdala and the temporal cortex is reciprocal [40], this learning enables the amygdala to influence
Conclusions
In summary, the model developed here provides a conceptual framework for understanding the functional contribution of the amygdala and vmPFC to the basis of care-based morality and, when dysfunctional, psychopathy. My main argument is that the amygdala enables the forms of learning necessary to care about the welfare of others, and, together with the vmPFC, enables this information to inform moral decision making. However, many questions remain unanswered. Although the functional response
Acknowledgements
This work was supported by the Intramural Research Program of the National Institutes of Health: National Institute of Mental Health.
References (70)
A cognitive developmental approach to morality: investigating the psychopath
Cognition
(1995)Ventral frontal deficits in psychopathy: neuropsychological test findings
Neuropsychologia
(1995)The emergence of psychopathy: implications for the neuropsychological approach to developmental disorders
Cognition
(2006)Limbic abnormalities in affective processing by criminal psychopaths as revealed by functional magnetic resonance imaging
Biol. Psychiatry
(2001)Functional differences among those high and low on a trait measure of psychopathy
Biol. Psychiatry
(2004)Neural correlates of social cooperation and non-cooperation as a function of psychopathy
Biol. Psychiatry
(2007)A cognitive neuroscience perspective on psychopathy: evidence for paralimbic system dysfunction
Psychiatry Res.
(2006)- et al.
Orbitofrontal cortex, associative learning, and expectancies
Neuron
(2005) Early amygdala damage disrupts performance on medial prefrontal cortex-related tasks but spares spatial learning and memory in the rat
Neuroscience
(2005)The neural basis of implicit moral attitude – an IAT study using event-related fMRI
Neuroimage
(2006)
Impaired decision making on the basis of both reward and punishment information in individuals with psychopathy
Pers. Individ. Dif.
Doing the right thing: a common neural circuit for appropriate violent or compassionate behavior
Neuroimage
Anger in healthy men: a PET study using script-driven imagery
Biol. Psychiatry
Neural correlates of maternal separation in rhesus monkeys
Biol. Psychiatry
Neurocircuitry models of posttraumatic stress disorder and extinction: human neuroimaging research – past, present, and future
Biol. Psychiatry
Preschool children's conceptions of moral and social rules
Child Dev.
Korean children's conceptions of moral and conventional transgressions
Dev. Psychol.
Morality: its structure, functions, and vagaries
Relations between psychopathy and persistent criminality – methodological and theoretical issues
Culture and moral development
Social interactions and the development of social concepts in preschool children
Child Dev.
Autism spectrum disorder and psychopathy: shared cognitive underpinnings or double hit?
Psychol. Med.
Longitudinal evidence that psychopathy scores in early adolescence predict adult psychopathy
J. Abnorm. Psychol.
The Hare Psychopathy Checklist – Revised
Aggression: Its Causes, Consequences and Control
Irritability in pediatric mania and other childhood psychopathology
Ann. NY Acad. Sci.
Impairment of social and moral behaviour related to early damage in human prefrontal cortex
Nat. Neurosci.
Callous-unemotional traits and conduct problems in the prediction of conduct problem severity, aggression, and self-report delinquency
J. Abnorm. Child Psychol.
The Emotional Construction of Morals
Sentimental Rules: On the Natural Foundations of Moral Judgment
The neural correlates of moral sensitivity: a functional magnetic resonance imaging investigation of basic and moral emotions
J. Neurosci.
An fMRI investigation of emotional engagement in moral judgment
Science
Autonomic components of vicarious conditioning and psychopathy
J. Clin. Psychol.
The psychopathic individual: a lack of responsiveness to distress cues?
Psychophysiology
A selective impairment in the processing of sad and fearful expressions in children with psychopathic tendencies
J. Abnorm. Child Psychol.
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